1 Annotation

Terry Foreman  •  Link

Protractor

"In geometry, a protractor is a square, circular or semicircular tool, typically in transparent perspex, for measuring angles. The units of measurement utilized are usually degrees (°).

"They are used for a variety of mechanical and engineering-related applications, but perhaps the most common use is in geometry lessons in schools.

"Some protractors are simple half-discs. More advanced protractors, such as the bevel protractor, have one or two swinging arms, which can be used to help measure the angle." http://en.wikipedia.org/wiki/Protractor

Log in to post an annotation.

If you don't have an account, then register here.

References

Chart showing the number of references in each month of the diary’s entries.

1669

  • Feb